Exoglucanase (CBH) is the rate limiting enzyme in the process of cellulose degradation. The carbohydrate binding module (CBM) can improve the accessibility of cellulase to substrate, thereby promoting the enzymatic hydrolysis of cellulase. In this study, the influence of CBM on the properties of GH6 exoglucanase from Chaetomium thermophilum (CtCBH) is systematically explored from three perspectives: the fusion of exogenous CBM, the exogenous CBM replacement of its own CBM, and the deletion of its own CBM. The parental and reconstructed CtCBH presented the same optimum pH (6.0) and temperature (60 °C) for maximum activity. Fusion of exogenous CBM increased the binding capacity of CtCBH to Avicel by 8% and 9%, respectively, but it had no significant effect on its catalytic activity. The exogenous CBM replacement of its own CBM resulted in a 12% reduction in the binding ability of CtCBH to Avicel, and a 26% reduction in the catalytic activity of Avicel. The deletion of its own CBM significantly reduced the binding ability of CtCBH to Avicel by approximately 53%, but its catalytic activity was not obviously reduced. These observations suggest that binding ability of CBM is not necessary for the catalysis of CtCBH.

外切葡聚糖酶（CBH）是纤维素降解过程中的限速酶。碳水化合物结合模块（CBM）可以提高纤维素酶对底物的可及性，从而促进纤维素酶的酶解。本研究中，煤层气对嗜热毛壳菌GH6外切葡聚糖酶特性的影响（CtCBH）从外源煤层气的融合、外源煤层气替换自身煤层气、删除自身煤层气三个角度系统探讨。亲本和重建的 CtCBH 具有相同的最佳 pH (6.0) 和温度 (60 °C)，以获得最大活性。外源 CBM 的融合使 CtCBH 与 Avicel 的结合能力分别增加了 8% 和 9%，但对其催化活性没有显着影响。外源 CBM 替代其自身的 CBM 导致 CtCBH 与 Avicel 的结合能力降低 12%，Avicel 的催化活性降低 26%。自身CBM的缺失使CtCBH与Avicel的结合能力显着降低约53%，但其催化活性并未明显降低。